No abstract

Background: Hip resurfacing had been utilized since the 1950s. The concept favored for young active patients owing to its proposed advantages. Revision rate of hip resurfacing in most national registries nearly 3.5%. Conversion to total hip replacement may be the correct option for old patients and those whose activity levels changed and the need for hip resurfacing no longer required.Purpose: The aim of this study is to assess the mid-term outcomes of converting failed hip resurfacing arthroplsty to total hip arthroplasty. Primary outcomes included improvement of Oxford, WOMAC, Harris and UCLA hip scores. Also; radiological follow-up has been evaluated for component stability or signs of loosening. Secondary outcomes included surgical site infection, residual groin pain, and heterotopic ossification. Most of patients (22 patients (88%) reported relief of pain and good to excellent patient satisfaction. Study design: Prospective case series study.Level of evidence: Therapeutic IV.Patients and Methods:Twenty–five patients (fifteen males) with failed hip resurfacing arthroplasty converted to total hip arthroplasty enrolled in this study. Mean age 56.8 years. Mean time to revision 36.8 months. Indications for revision included: femoral neck fractures (10 cases), femoral neck thinning (3 cases), component loosening (4 cases) component dislocation (2 cases) persistent groin pain and clicking (3 cases) and wear of components (3 cases). Nineteen patients revised both components while remaining six underwent revision of femoral component only. Results:The average duration of follow up was 26.8 months (28-48 months). The study was an intermediate term follow-up. Clinical outcome evaluated through Oxford, WOMAC, Harris and UCLA hip scores. Preoperative scores 21.3, 78.3, 35,7 and 2 respectively improved to 39.8, 11.1, 92.3 and 7 respectively at last follow-up representing statistically significant improvements over pre-operative scores (p < 0.0001 for each score) Radiological follow-up evaluated for component stability or signs of loosening. No cases of neurological, vascular, deep infection or implant failure. There were 3 cases (3%) with complications. one case complicated by surgical site infection with serous drainage for more than seven days and treated with oral antibiotics and daily dressings. One case had residual groin pain, and third case had mild heterotopic ossification. All patients were satisfied particularly by their pain relief. Average post operative Oxford, Harris and WOMAC hip scores were 17.4, 89.8 and 6.1 respec-tively. representing statistically significant improvements over pre operative scores (p < 0.0001 for each score)Conclusions: study shows conversion of hip resurfacing to THA has high satisfaction rates. These results compare favorably with those for revision total hip arthroplasty